This invention relates to an improved back pressure regulating valve for use with pumps such as high pressure water jetting pumps, and more particularly to valves suitable for applications utilizing an elongated tapered poppet and an accommodating poppet seat to reduce fluid velocity in the valve and having a gas charged actuator with a damping chamber.
Hydraulic jetting, wherein fluid such as water, is pumped at high pressures through jetting nozzles, is used for a variety of applications such as cleaning of industrial equipment, heat exchangers, and boilers. Hydraulic jetting is also used for drilling and cutting a large variety of materials.
In many hydraulic jetting applications, one or more hand-operated, or machine-operated lances, or nozzles, are used. The operators normally trigger these lances on and off many times during a jetting operation. Thus, a highly responsive flow control device is needed to modulate flow from such a pump being used to pressurize the water, or other liquid, that is being used on demand in a particular jetting application. An illustrative pump is disclosed in U.S. Pat. No. 5,127,807 which is particularly suitable for providing pressures up to 20,000 psi (1,400 kg/cm.sup.2). For applications requiring working pressures of approximately 10,000 psi (700 kg/cm.sup.2) or less, plunger style pumps such as HT-150 and HT-400 plunger style pumps available from Halliburton Energy Services, a division of the assignee hereof, are commercially available. Additionally, there are a variety of commercially available pumps of various designs suitable for a wide variety of applications requiring such a flow control device.
In practice, it is required that the flow control device be able to maintain a substantially constant system pressure in response to significantly changing flow rates. Thus it is desired that the flow control device be able to endure, or better yet, avoid the destructive effects of the flow of liquid through the flow control device at speeds ranging from near sonic to supersonic. A representative priorly known flow control device is disclosed in U.S. Pat. No. 5,065,789 assigned to the assignee hereof, and which is incorporated herein as a reference.
Priorly known flow control valve devices, including the poppet-type valve disclosed in U.S. Pat. No. 5,065,789, are susceptible to erosive wear to various degrees, depending on the particular valve. Thus, there remains a need within the art to further reduce the amount of erosive wear experienced by poppet-type valves when operating at pressures ranging from 0 to 20,000 psi (1,400 kgs/cm.sup.2).
There also remains a need for a poppet-type valve which can be manufactured with fewer components than previously required in the construction of priorly known valves.
There also remains a need for components made with less expensive materials as compared to the materials required to construct components for priorly known poppet-type valves.
There further remains a need for a poppet-type valve in which tolerances between certain components are not as critical as compared to the tolerances required with previously known valves.
These needs and others are fulfilled by the present invention disclosed herein.